1. A substantial increase in the mutation rate in E.coli would be caused by:
1 A mutation in the mutS gene.
2 A mutation in the rpsE gene.
3 Exposure to a bacteriophage, such as phagelambda.
4 Growth in a liquid culture.
2. Which of the following could makebacteria resistant to the bacteriophage λvir?
1 A mutation in lamB.
2 Transformation into a lysogen.
3 Growth on MacConkey agar.
4 A mutation in ompC.
3. Bacterial cells resistant to λvirare plated onto a maltose MacConkey plate and colorless coloniesare observed on the plate the following day. Which of the followingbest represents the genotype of the bacteria comprising thecolorless colonies?
1 lamB¯
2 malP¯
3 malQ¯
4 malT¯